Objectives
 Identify the following as they pertain to external fixation:
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–
Advantages & disadvantages
Indications
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–
Types of frames
Biomechanics stability
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Pre-operative planning
Common complications

External Fixator
 A device placed outside the skin that stabilizes bone fragments with pins or wires connected to bars
 “Relative stability “
 Healing with callus

External Fixation
Advantages
 Minimal damage to blood supply
 Minimal damage to soft tissues
 Fixation is away from site of injury
 Good option when significant infection risk

External Fixation
Disadvantages
 Restricted joint motion
 Pin tract infection
 Cumbersome
 Inadequate stability for certain fractures

Indications
 Most commonly used:
– Tibia
– Distal radius
 Less commonly used:
–
–
Femur
Humerus
– Forearm

Indications
 Open fractures
 Closed fractures with soft tissue compromise
 Periarticular fractures
 Polytrauma/Damage control
 Pelvic fractures
 Children’s fractures

Open Fractures
 Avoids injury site
 Avoids additional injury to soft tissues and vascularity

Open Fractures

Open Fractures
 Segmental bone loss

Open Fractures
 Fractures needing nerve or vessel repair

Closed Fractures with Soft
Tissue Compromise
 Swelling
 Fracture blisters

Closed Fractures with Soft
Tissue Compromise
 Crush injuries
 Burns

Closed Fractures with Soft
Tissue Compromise
 Compartment syndrome

Periarticular Fractures
 Severe fractures with joint involvement and shaft extension

Periarticular Fractures
•
Spanning ex-fix if axially unstable

Periarticular Fractures
 Hybrid Fixator:
– Thin wires near joint
– Pins (Schanz Screws) in shaft

Periarticular Fractures
 Reduce and fix the joint surface
 Span the diaphyseal segment without disturbing soft tissues

Periarticular Fractures
 External fixation can be combined with internal fixation

Polytrauma
 Temporary stabilization of long bone injuries in unstable patient
– Minimally invasive
– Decreases bleeding
– Pain control
– Nursing care
– “Damage control”

Pelvic Fractures
 Temporary stabilization for closed fractures
 Controls hemorrhage
 Decreases clot shear

Pelvic Fractures
 Open pelvic fractures = “The lethal injury”

Pelvic Fractures
 Quick application
 Open or percutaneous pin insertion
 Easily removed for definitive ORIF

Children’s Fractures
 Femoral fractures
 One alternative to weeks of skeletal traction
 Used less with use of flexible nails

Children’s Fractures
 Pin placement must avoid growth plate
 Watch for pin tract infection
 Occasional joint stiffness

External Fixation

Fixator construct will depend on treatment strategy:
–
Emergency care
– Provisional care
– Definitive care

External Fixator Constructs
 Uni-plane
 Bi-plane
 Multi-plane
 Ring

•
Uni-plane
•
Bi-plane
• Multi-plane

Uni-plane Fixator
Single Bar

Uni-plane Fixator
“Z Frame”

Uni-plane Fixator
Double Stacked

Bi-plane Fixator

Multi-plane Fixator

Spanning External Fixation
 Built as uni- and multi- plane constructs
 Areas prone to soft tissue problems
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–
Knee
Ankle
– Open Fractures
 When multiple injuries prevent definitive fixation

Spanning Ex Fix
 Adjunct to Internal Fixation
– Temporary
– Definitive

Increase Stability
 Pins
– Larger diameter
– More pins
– Closer to fracture site

Increase Stability
 Bars:
– Closer to limb
– More bars
– Second plane at right angle to decrease torsion
(twisting)

Increase Stability
 Rings:
– Smaller is stiffer

Use smallest diamaeter ring possible but allow for swelling
– More rings = more stable

External Fixation Anatomy
 Safe pin placement
 “Safe corridors”
 Know your anatomy to safely place pins!

Intraop Setup
 Circumferential prep of entire limb
 Radiolucent table
 C-arm

Intraop Setup
 Associated procedures
 Irrigation
 Debridement
 Internal Fixation
 Bone graft

Intraop Setup
 Adequate fixator components
 Cannulated screws
 Large/small fragment sets

Intraop Technique
 Keep bars close to bone but…
 . . . allow access for soft tissue care
 Allow for swelling
 Can be re-adjusted as needed

Complications

Neurovascular injury
 Pin loosening
 Pin tract infection
 Joint stiffness
 Malalignment
 Malunion
 Nonunion

Complications
 Pin tract infections:
–
–
–
–
Most common complication
Avoid fracture area
Don’t “burn” bone – pre-drill
Insert pin completely
– Release skin

Complications
 Know where pins are going!